Over time building piping systems such as those used in commercial buildings, apartment buildings, condominiums, residential homes and the like, that have a broad base of users commonly develop problems with the building pipes such as with their water and plumbing pipes, and the like. Presently when a failure in a piping system, such as a leak occurs the repair method can involve a number of separate repair applications. Those repair applications often involve a specific repair to the area of failure such as replacing that section of pipe or the use of a clamping devise and a gasket. However, these popular types of repair applications can cause additional problems with the building piping system.
Problems such as low water flow, or discolored water can result from build-up of materials, and the like occurring inside the pipe that has not been properly cleaned. Additional problems associated with installing a cut pipe that has not been reamed or deburred can cause water turbulence as the water flows over an unreamed burr or lip left inside the pipe. Such problem can be a prime cause of erosion corrosion inside the pipes which quickens the deterioration and lifespan of the pipes.
Traditional techniques to correct for a potential leak, an actual leak, buildup or blockage or reducing or removing an unreamed lip or burr have included replacing some or all of a building's pipes. In addition to the large expense for the cost of the new pipes, additional problems with replacing the pipes can include the immense labor and construction costs that must be incurred for these projects. In addition the down time to the piping systems undergoing the repairs adds extra expense and discomfort to those needing to use the piping systems.
There are additional complications since most piping systems are located behind finished walls or ceilings, under floors, in concrete or underground. From a practical viewpoint simply getting to the problem area of the pipe to make the repair can create the largest problem. Reaching to the pipe for making repairs can require tearing up the building, cutting concrete and/or having to dig holes through floors, the foundation or the ground. These labor intensive repair projects can include substantial demolition of a buildings walls and floors in order to access the existing piping systems. For example, tearing out of the interior walls to access the pipes is an expected result of the demolition necessary to fix existing pipes.
Additionally, there are usually substantial time-consuming costs for removing the debris and old pipes from the worksite. With these projects both the cost of new pipes, the ancillary repair to the building and the additional labor to install these pipes require expensive and time consuming expenditures. Further, there are additional added costs for the materials and labor to replumb these new pipes along with the necessary wall and floor repairs that must be made after the repairs to clean up for the demolition effects.
Under current repair applications, just reaching at and fixing a pipe behind drywall is not completing the repair project. The drywall or wall covering surfaces must also be repaired, and just these types of repairs can be extremely costly. Additional expenses related to the repair or replacement of an existing piping system will vary depending primarily on the location of the pipe, the building finishes surrounding the pipe and the presence of hazardous materials such as asbestos encapsulating the pipe. Furthermore, techniques for making piping repair take considerable amounts of time which results in lost use and lost revenue from tenants and occupants of commercial type buildings since tenants cannot use the buildings until the repairs are done.
Finally, the current pipe repair techniques are usually only temporary. Even after encountering the cost to repair the pipe, the cost and inconvenience of tearing up walls or grounds and if a revenue property the lost revenue associated with the repair or replacement, the repaired and/or new pipe(s) will still be subject to the corrosive effects of water type fluids that flow through the pipes.
Governments and municipalities are now beginning to recognize and deal with corrosive effects of metal building piping systems. On Sep. 30, 2005, the State of California recognizing the negative effects of corrosive water on metallic piping systems signed into law Assembly Bill 1953, which reduces the allowable amount of lead in potable water delivery systems (such as through metal pipes) to 0.25%. The bill states: “No person shall introduce into commerce, for use in California, any pipe, pipe or plumbing fitting, or fixture intended to convey or dispense water for human consumption through drinking water or cooking that is not lead free, as defined in subdivision (e). This includes kitchen faucets, bathroom faucets, and any other end-use devices intended to convey or dispense water for human consumption through drinking or cooking.”
Over the years many different attempts and techniques have been proposed for cleaning water type pipes with chemical cleaning solutions. See for example, U.S. Pat. No. 5,045,352 to Mueller; U.S. Pat. No. 5,800,629 to Ludwig et al.; U.S. Pat. No. 5,915,395 to Smith; and U.S. Pat. No. 6,345,632 to Ludwig et al. However, these systems generally require the use of chemical solutions such as liquid acids, chlorine, and the like, that must be run through the pipes as a prerequisite prior to any coating of the pipes.
Other systems have been proposed that use dry particulate materials as a cleaning agent that is sprayed from mobile devices that travel through or around the pipes. See for example, U.S. Pat. No. 4,314,427 to Stolz; and U.S. Pat. No. 5,085,016 to Rose. However, these traveling devices generally require large diameter pipes to be operational and cannot be used inside of pipes that are less than approximately 4 inches in diameter, and would not be able to travel around narrow bends. Thus, these devices cannot be used in small diameter pipes under 2 inches in diameter that also have sharp and narrow bends.
In some cases, compressed air carrying particles of abrasive material is blown through the pipe. Such a method is described, for example, in U.S. Pat. No. 5,622,209 to Naf and in U.S. Pat. No. 5,007,461 to Naf. In the Naf U.S. Pat. No. 5,007,461 the abrasive cleaning method described involved the use of compressed air alone with a continuous feed of abrasive material. And in the U.S. Pat. No. 5,622,209 to Naf, the interior of the pipe is subsequently coated with an adhesive resin, such as an epoxy resin, which is also applied by use of compressed air to blow it through the pipe.
The Naf patents described continuously blowing, large amounts of sand (approximately 200 Kg) that required extensive amounts air volume and pressure. Pre-drying took approximately 30 minutes, and a special separator was installed at the conduit outlet; the fine solid material exiting (apparently mainly calcium deposits and rust) entered a special separator. Then a feeding device for the abrasive medium (dry regular sand with a grain size of 2 to 4 mm) was installed in the conduit between the compressor and the air inlet. A separator with a cyclone separator with pressure gauge and regulating valve was installed at the air outlet. Then work was done for approximately 8 minutes at a mean overpressure of approximately 1 atmosphere at highest compressor output and greatest abrasive medium feed. At the end of blowing approximately 200 kg of abrasive medium had been blown through the conduit to be cleaned. At the end of blowing, the air exiting at the separator had a temperature of −50.degree. C. These elaborate blowing processes using great amounts of abrasive material are prone to problems.
These processes of using compressed air in this way can only be used on relatively small diameter pipes, and this cleaning technique easily results in blocking of the pipe, or major leaks in the pipe when weakened after cleaning by constant high pressure and large amounts of abrasive material being used. Also, the pipes are often not be adequately cleaned by such a processes when major frictional resistance occurs in the pipe system.
U.S. Pat. No. 5,924,913 of Reimelt attempts to overcome these problems by using a suction at one end of a section of pipe. Reimelt specifically discusses the problems with NOT wanting to use compressed air supplies for renovating pipes since they result in damage to the interior of the pipes, blockages in the pipes and result in pollution. See column 2, lines 39-62. However, the Reimelt technique of only using a suction (low pressure) at one end of a pipe section can also result in blockages and other problems. When an abrasive agent is repeatedly moved back and forth, it will gradually become mixed with the debris removed from the pipe surface, diluting or reducing the cleaning effect. Additionally, the Reimelt techniques require the use of heating devices such as wires that must be pulled or towed through pipe sections which adds additional expense and can also result in the dragged heating device damaging the interior of the pipes or even getting stuck in the pipes. Also, the Reimelt technique cannot be used with cleaning entire piping systems having bends and t-branches cannot be cleaned unless every pipe section is potentially taking apart and separately cleaned. Also, Reimelt cannot be used with small pipes that need to be cleaned since the suction and heating devices cannot easily pass through pipes smaller than approximately 2½ inches in diameter.
Thus, the need exists for solutions to the above problems where providing a processes of abrasive cleaning in small diameter pressurized pipes, up to 2 inches in diameter, that can be deburred, cleaned effectively and efficiently, in-place, without clogging the pipe during the cleaning process, with minimal damage to the pipe and without large quantities of abrasive material being used. A further application of a barrier coating and sealing leaks is accomplished in piping systems in a single operation, further protecting the piping system and all it's components from the effects of corrosion, thereby reducing the leaching of heavy metals such as lead into the water supply.